Communism is a political and economic system that emerged in the 19th century and gained currency as a response to the problems of industrialization in Western Europe and the United States. Communism centered upon common ownership of property and distribution of goods and services based on need and not individual wealth or social class. Based in part upon utopian and socialist writings, communism was presented as a form of socialism in the Communist Manifesto, written by Karl Marx and Fredrich Engels in 1848.

With the Russian Revolution in 1917, communism became the ideological framework that would guide the Soviet Union and eastern bloc nations for the next 60 years. Revolutionaries in China turned to a form of communism in their rise to power in 1949 and activists in Korea, Vietnam, and Cuba adopted communism in the 1950s and 1960s to justify their crusade and offer a form of governing. In the United States and Western Europe, small, organized communist organizations sought political power at various times but never achieved any significant degree of electoral success. With economic pressures and demands for democratic reforms, the Soviet Union collapsed in the early 1990s and communism became a minor political party in Russia, in former Soviet satellite nations, and in eastern bloc nations.

Although many Americans in the early 20th century objected to hardships faced by the working class and excessive consumption by the wealthy, they did not turn to communism in large numbers. Most sought reform, not revolution, either by joining socialist organizations and/or labor unions or by supporting the reforms offered by the populists of the late 19th century and later the progressive movement platform in the early 20th century. Even the Great Depression of the 1930s, with massive unemployment and economic dislocation, failed to energize a significant communist movement in the United States.

After World War II, the United States and the Soviet Union competed for global power in a “cold war” which pitted the values of Western democracy against communism. In American political culture, communism became a dominant theme in both campaign and policy-making communication. Conservative leaders in the United States, beginning with Richard Nixon in the 1950s, Barry Goldwater in the 1960s, and Ronald Reagan in the 1970s and 1980s, presented the battle against communism as the defining ideological crisis of the age. Powerful metaphors describing the destructive force of communism were pervasive in political debates in post–World War II America, including such terms as the iron curtain, containment, the domino theory, and the cancer of communism.

The dismantling of the Soviet Union in the early 1990s and economic reforms in China and Vietnam left few communist governments in power around the world and no organized effort to install communism in Western democracies.